According to WHO, the prevalence of raised blood pressure is highest in Africa, where it was 46 per cent for both sexes combined. Though ere are no records on the recent findings, a study done in 2000 showed Tanzania’s prevalence of hypertension to be 37.3 per cent in men and 39.1 per cent in women in Ilala District in Dar-es-Salaam and 26.3 per cent in men and 27.4 per cent in women in a rural district in Kilimanjaro Region.
This prevalence is high and sadly out of those found to be hypertensive only a mere 20 per cent were aware of their diagnosis, only about 10per cent received treatment and out of those on medication, only 1 per cent had their blood pressure controlled to target. This shows that not only is hypertension underdiagnosed but even when it is, it is poorly managed.
Hypertension, a term used for raised blood pressure (BP) is a disorder that occurs when the blood pressure in arteries is persistently elevated. It is estimated to have a global prevalence of around 40 per cent in persons aged 25 and above.
However, this is undoubtedly an underestimate as most people with raised blood pressure are unaware of the diagnosis. Also, the number of people with uncontrolled hypertension may be expected to increase because of population growth and ageing.
In the past, it was believed that hypertension and cardiovascular ailments were mainly a disease of the affluent. A survey undertaken in an urban slum in Kenya showed the prevalence of hypertension to be 22.8 per cent which was high. Urbanization is a key driver of the evolving epidemic and these rates are expected to rise.
Hypertension is now the leading cardiovascular problem in Africa and is also a major risk for coronary heart disease and stroke. Other complications of raised blood pressure are heart failure, peripheral vascular disease, renal and visual impairment.
In Sub-Saharan Africa, hypertensive end-organ-damage is a major source of morbidity and mortality and increases with age. A study of rural and urban Tanzania reported rates of stroke mortality higher than those of England and Wales, with untreated hypertension suggested to be an important causative factor.
Blood pressure is measured by two components which are systolic and diastolic, implying maximum and minimum levels, respectively. A normal BP should be less than 140 systolic and less than 90 diastolic.
These should be measured with a BP cuff that fits properly neither too tight nor too loose, with the patient relaxed, seated still and upright and the upper arm at the same level as the heart and feet flat on the floor. If possible, readings should preferably be multiple and preferably at the same time daily.
Hypertension may be classified into primary or secondary. With primary hypertension, also called essential hypertension, development may be due to environmental or genetic causes.
This is the most common form and usually affects those above the age of 40. Secondary hypertension is that which occurs due to a predisposing condition such as renal, vascular or endocrine disorders and is less common accounting for about 2-10 per cent.
Risk factors for hypertension include age (the risk increases as one ages), race (African- American more than whites), family history, being overweight or obese, not being physically active, using tobacco products, excessive alcohol intake, too much salt (sodium) and too little potassium in the diet.
Also, after the age of 65, women are more likely to have high BP than men. Probable risk factors for hypertension include, stress which can temporarily increase your BP but hasn’t been proven to cause hypertension.
Also, sleep apnea which is a condition when tissues in the throat collapse and block the airway when sleeping and the person experiences breathing difficulties, forcing him/her to wake up. This condition has been associated with a raised BP.